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HEMISKI Zbirka re{eni zada~i REAKTORI 3

HEMISKI Zbirka re{eni zada~i REAKTORI 3

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[esti del. Industriski <strong>re</strong>aktori<br />

H r ( T ) 92215<br />

( 54<br />

0,<br />

0365T<br />

) dT<br />

H<br />

r<br />

298<br />

( T ) 77743<br />

54T<br />

0,<br />

01825T<br />

T<br />

2<br />

kJ/kmol.<br />

Vo toplinskiot bilans (11) proizvodot na koeficientot<br />

na p<strong>re</strong>nos na toplina i specifi~nata povr{ina na toplinska<br />

razmena }e se zeme vo dad<strong>eni</strong>te ramki:<br />

UaV = 20640–24570 kJ/(m 3 ·h·K).<br />

Za granici na integrirawe na ravenkata (11) se zemaat,<br />

V = 0, T T T 694K<br />

i Vfinal = Vkat = 4,07 m 3 , T = Tizlez. V 0<br />

o<br />

T<strong>re</strong>ba da se naglasi deka ovaa vlezna temperatura mo`e<br />

da se nagoduva, da bide poniska ili povisoka. Taa e zemena od<br />

literaturata kade {to, isto taka, nekoi parametri na procesot<br />

se nagoduvaat.<br />

– Ravenka na toplinski bilans na smesata so <strong>re</strong>aktanti:<br />

Ovaa bilansna ravenka }e sodr`i samo dva ~lena: 1) toplinata<br />

{to vo edinica v<strong>re</strong>me se p<strong>re</strong>nesuva niz yidovite na cevkite<br />

(od <strong>re</strong>akcionata smesa {to se dvi`i niz katalizatorskiot<br />

sloj odgo<strong>re</strong> sp<strong>re</strong>ma dolu kon smesata so <strong>re</strong>aktanti, koja se dvi`i<br />

vo cevkite oddolu sp<strong>re</strong>ma go<strong>re</strong>) i 2) toplinskiot protok {to go<br />

nosi strujata na smesata so <strong>re</strong>aktanti (se zag<strong>re</strong>va). Bidej}i dvi-<br />

`eweto na dvete strui e vo sprotivni nasoki (protivstrujno<br />

dvi`ewe), bilansnata ravenka }e glasi vaka:<br />

dT<br />

dV<br />

Ua<br />

( T<br />

f V f<br />

<br />

4<br />

FioC<br />

P,<br />

if<br />

i1<br />

T )<br />

. (12)<br />

Razlikata vo oznakite na specifi~nite toplini vo ravenkite<br />

(11) i (12), CP,i nasproti CP,if, poka`uva deka nivnite<br />

isti temperaturni zavisnosti t<strong>re</strong>ba da bidat p<strong>re</strong>tstav<strong>eni</strong> vaka:<br />

za ravenkata (11) p<strong>re</strong>ku temperaturata na <strong>re</strong>akcionata smesa T,<br />

dodeka za ravenkata (12) p<strong>re</strong>ku temperaturata na smesata so <strong>re</strong>aktanti<br />

Tf. Za proizvodot na koeficientot na p<strong>re</strong>nos na topli-<br />

595

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